**4.1** *Vitis amurensis*

*V. amurensis*, which originated in north-eastern China, is now commercially cultivated in many places. The most important trait for this species is cold resistance. *Vitis amurensis* has a strong root system and high growth vigor, allowing it to survive at temperatures as low as 40°C. Besides, this species also showed high resistance to many diseases such as grape white rot and grape anthracnose [12]. Thus, it has been used as a disease-resistant stock as well as the most powerful coldresistant rootstock to breed materials for resistance to biotic and abiotic environmental factors [12], and it is considered to be an effective way to save inputs in vineyard management by avoiding burying the vines.

Since the 1950s, significant progress has been made in understanding and utilizing wild *V. amurensis* grape germplasm resources in China. Grape researchers conducted a series of selection and domestication experiments on the *V. amurensis* species in Northeast China, and after many years of effort, they have selected a series of good varieties and types (**Figure 3**), as well as a series of work on cultivation and expansion on this variety [13].

As a wine grape, the *V. amurensis* fruit has a unique aroma and distinctive taste with high acidity and bitterness thus was used to make sweet wines [12, 14]. Nowadays, with the breeding of new varieties, *V. amurensis* and its hybrids can be used to make sparkling wine [15], rose wine [16], and ice wine [11]. Some novel techniques, such as carbonic maceration can also be used to improve the quality of *V. amurensis* wine [17].

When Bei Bing Hong (a variety of *V. amurensis*) was used to produced sparkling wine, its esters, carbonyls, alcohols, and terpenes contributed significantly to the aroma profile of the wine. The typical aroma characters of Bei Bing Hong sparkling wine are fruity aromas such as apple, apricot, pear, strawberry, cherry and sweet melon [15]. A mixed brewing method was used to produce rose wine from *Vitis amurensis* Rupr cv. Gongzhubai (white) and Beibinghong (red) grapes [16]. The

#### **Figure 3.**

fruit of each variety was pressed and the must fermented at low temperatures (11 12°C). By combining 8% and 12% of Beibinghong wine with Gongzhubai wine, a rose wine with elegance and aroma complexity was produced [16].

Lan [11] studied the evolution of free and glycosidically bound volatile compounds in 'Beibinghong' grape berries during on-vine, over-ripening, and freezing processes. The results showed that the aroma profiles of 'Beibinghong' icewine berries were characterized by C6 compounds, higher alcohols, and terpenoids in free fractions as well as carbonyl compounds, higher alcohols, C6 alcohols, and terpenoids in bound fractions. A striking alteration of the volatile profile of C6 alcohols, higher alcohols, and oxidative terpene derivatives occurred at sub-zero temperatures. These changes were attributed to a series of reactions (biotransformation, oxidation, and anaerobic metabolism) induced by water loss and particularly, freeze–thaw cycles [11].

Anthocyanins are responsible for the color of grapes and wine. Zhao [10] analyzed the anthocyanin profiles of grape berries of *Vitis amurensis*, its hybrids, and their wines. It was found that the anthocyanin profile of the grape cultivars consisted of 17 anthocyanins, including 11 anthocyanin monoglucosides and six anthocyanin diglucosides. However, the wines produced a slightly different result in anthocyanin distribution in the corresponding wines where 15 kinds of

anthocyanins, including six diglucosides and nine monoglucosides were detected [10]. Furthermore, pelargonidin-3,5-diglucosides was also found in the grapes and their corresponding wines.

Additionally, Li [9] also revealed that *Vitis amurensis* and its hybrids wines had a higher phenolic percentage of non-coumaroylated 3, 5-O-diglucosidic anthocyanins, while *V. vinifera* wines had a higher phenolic percentage of flavan-3-ols and 3-O-monoglucosidic anthocyanins.
